The invention relates to a portable keyboard, and particularly a keyboard that allows users to bend, fold or twist into a small size to facilitate storing and carrying.
Portable personal electronic data processing devices such as notebook computers, Personal Digital Assistants (PDAs) and the like allow users to process or read information anywhere anytime. Coupling with wireless data communication technology, obtaining information is even easier. With rapid technological innovations and developments, those portable electronic data processing devices have become leaner, and are more convenient for users to carry around.
In order to reduce the size of portable electronic data processing devices, many designs have to be changed. Taking input devices such as keyboards for instance, keys on notebook computers have to be shrunk and laid more closely together. On PDAs, the display devices have adopted touch screens and input is done by using stylus writing on the screen through pressure contact. In comparison, keyboards of general desktop computers have a more desirable interval between keys. Users may operate the keys on the keyboard with both hands. This is still the fastest and most comfortable input method at present, and is most commonly used. However, keyboards on notebook computers are reduced to a smaller size, and keys are smaller and laid closer to each other, to people who are used to conventional keyboards of desk top computers, notebook computer keyboards are not comfortable to use. As a result, input speed suffers. Moreover, the layouts of some keys on notebook computer keyboards are different from that of conventional desktop computer keyboards. PDAs have only a few keys and a touch screen for inputting, and are not suitable for entering large amounts of data. Their reduced sizes have compromised input convenience.
As notebook computers or PDAs have increasingly become indispensable tools for many people, in order to resolve these input problems, some manufacturers have developed and introduced various types of portable externally connected keyboards.
For instance, U.S. Pat. No. 6,174,097 discloses a foldable keyboard which is divided into a plurality of sections and employs turning shafts to connect various sections and allow them to fold and close against one another. When in use, the various sections may be unfolded. However such type of foldable keyboard still occupies substantial space when folded. Moreover, the pivotal connections of the turning shafts are prone to rupture. It is not a desirable keyboard design.
U.S. Pat. Nos. 6,265,993 and 5,220,521 disclose keyboards that can be wound in a roll. The proposed keyboards consist of a plurality of plastic membranes. The plastic membranes are printed with silver paste circuits. Through the designs of the plastic membranes and silver paste circuits, keyboards may be wound into a roll. However their pliability has limitations. When the roll is wound into too small of a diameter or even folded, the plastic membranes cannot be returned to their normal condition. Even when the plastic membranes are returned to their normal condition, the silver paste circuits could be stretched too much and broken, resulting in malfunction of some keys. Furthermore, these keyboards can only be bent into a curve but cannot be folded or stacked. In order to avoid compression or impact when carried, special storage barrels must be designed and provided for holding the rolled keyboards. Thus they are also not desirable keyboard designs.
U.S. Pat. Nos. 5,666,112 and 5,616,897 disclose pliable inflation keyboards. Although the keyboards can be bent, a portable inflation device has to be carried with each keyboard to inflate the keyboard when in use. They also are not desirable designs for portable keyboards.
The primary object of the invention is to provide a portable keyboard that allows users to bend, fold or twist.
The portable keyboard according to the invention includes a key body made from highly pliable and elastic materials and a circuit body. The key body includes a plurality of key caps. The key caps have conductive rubber embedded therein to form electric contacts. The circuit body has connection lines made from conductive rubber embedded therein. The structural elements of the keyboard of the invention are all highly pliable, thus may be bent, folded, or twisted without affecting electronic characteristics.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings. The drawings are only to serve for reference and illustrative purposes, and are not intended to limit the scope of the invention.